Silicon-base mesostructured cellular foam (MCF) was synthesized and employed as support for immobilization of lipase LVK-S. The immobilized lipase had been prepared by incorporation of lipase and MCF with 20-30 nm channels in phosphate buffer for 10 h, washing, centrifugal filtering and vacuum drying. The lipase powder before and after immobilization was analyzed by IR- and UV- spectrum, indicating that lipase had been fixed, and the activity of immobilized lipase was measured by assay of fatty acid releasing rate using pure olive oil as substrate, and was 480 U · g-1. Pre-treated waste cooking oil and methanol was mixed with ratio of six in mass, then reaction was initiated by adding 0.2% (mass) immobilized lipase powder at 281 under stirring condition. The results obtained by analysis of gas chromatograph displayed that there were at least 5 kinds of main FAMEs (fatty acid methyl ester) containing in broth, and yield of total FAME was about 0.83. Further evaluation of activity for immobilized lipase using waste cooking oil and pure olive oil as substrate showed that the residual activity was kept over 90% for pure olive oil, but only 61% for waste cooking oil, indicating that some components in waste cooking oil could decrease activity of lipase. So, it would be hopeful and useful to keep activity of immobilized lipase in reaction conditions if these harmful components could be removed by pre-treatment of wasted cooking oil.
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